Which sentence has an adjective clause?

mike rode his bike on mountain trails because he found them challenging.

gary donated to charity whenever he could.

liz, who could always make people laugh, was loved by the whole block.

ever since adam was a little boy, he had his father in the fields.

honestly, school in itself just seems to be a huge waste of time. a lot of people graduate but still end up not doing anything in college anyways, which really makes the whole point of graduating seem useless. i'd rather not bring anyone's hopes up then. what i'd recommend is for whoever's reading this to simply drop out.

i mean, kanye did it. he said something along the lines of, "don't let society tell you what to do." now, he's obviously a very successful person, and since his album is called the college dropout i guess he never really had to go through all that nonsense in order to become a millionaire. the same goes for anyone else then.

the answer is academic paper

and the second should be college professor